Segment Information - Revenue and Operating Income By Segments (Details) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)		Dec. 31, 2013 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment										4
Revenue by segment		$ 1,680	$ 1,613	$ 1,604	$ 1,476	$ 1,768	$ 1,647	$ 1,658	$ 1,518	$ 6,373	$ 6,591		$ 6,123
Operating income by segment										830	820		717
Pension expense										464	152		(78)
Other adjustments	[1]									231	315		129
Income from operations		$ 138	$ 168	$ (266)	$ 95	$ 35	$ 41	$ 169	$ 108	135	353		666
Restructuring and other asset-related charges										74	160		0
Acquisition Related Amortization Costs Included in Other Adjustments										125	119		65
Acquisiton Related Costs Included In Other Adjustments										11	27		46
Acquisition Related Purchase Price Adjustments										0	6		15
Legal Costs for OFAC and FCPA Investigations										1	3		3
Reserve related to subcontract in Middle East Africa										20	0		0
Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue by segment										3,319	3,561	[2]	3,115
Operating income by segment										518	543	[2]	356
Retail Solutions [Member]
Segment Reporting Information [Line Items]
Revenue by segment										2,001	2,008		2,034	[3]
Operating income by segment										156	155		205	[3]
Hospitality [Member]
Segment Reporting Information [Line Items]
Revenue by segment										686	659		626
Operating income by segment										115	91		100
Emerging Industries [Member]
Segment Reporting Information [Line Items]
Revenue by segment										367	363		348
Operating income by segment										41	31		$ 56
Digital Insight [Member]
Segment Reporting Information [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual										349
Segment Operting Income of Acquiree Since Acquisition										$ 104
Retalix [Member]
Segment Reporting Information [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual											298
Segment Operting Income of Acquiree Since Acquisition											$ 53

[1] The following table presents the other adjustments for NCR for the years ended December 31:In millions 2015 2014 2013Restructuring plan $74 $160 $—Acquisition-related amortization of intangible assets 125 119 65Acquisition-related costs 11 27 46Acquisition-related purchase price adjustments — 6 15OFAC and FCPA investigations 1 3 3Reserve related to subcontract in MEA 20 — —Total other adjustments $231 $315 $129

[2] From the acquisition date of January 10, 2014 through December 31, 2014, Digital Insight contributed $349 million in revenue and $104 million in segment operating income to the Financial Services segment.

[3] From the acquisition date of February 6, 2013 through December 31, 2013, Retalix contributed $298 million in revenue and $53 million in segment operating income to the Retail Solutions segment.